World Battlefronts: BATTLE OF THE SEAS: Alias Graph

A British plane doggedly making
the rounds of patrol off Iceland in 1941 sighted an enemy submarine.
The plane made a run, dropped depth charges, circled to watch results.
Suddenly the submarine surfaced and to the flyer's surprise quickly ran
up a white flag (later found to be the commander's shirt). The U-570 was boarded by the
British, found virtually undamaged.

Announced the Admiralty last week: The U-570 was a pretty good
submarine. Manned by a specially trained British crew and renamed the
Graph, it had made several successful trips for the Royal Navy,
destroyed one real German-run U-boat,...